This invention relates to an improvement on the present seat belt design in use on motor vehicles and other modes of transportation.
The seat belt now in use often becomes twisted while trying to engage it into the locked position. If it is badly twisted, it has to be disengaged and straightened before it can be properly placed across the body. Often a person using the seat belt will not bother with this corrective procedure and leave the twisted seat belt in place. This could not only be quite uncomfortable to the body, but it could be injurious to the body in the event of a collision.
Vehicle service manuals indicate that a twisted belt is an undesirable condition.
Occasionally upon disengagement, the seat belt, if badly twisted, will become jammed in the housing while retracting to its unused position. It can be a frustrating and time-consuming effort to free the seat belt from this jammed condition.
Although it is bad safety procedure, some drivers will proceed to drive off before fully engaging their seat belt. A twisted seat belt, occupying the attention of the driver at this particular moment, could result in a collision. The twist-free seat belt would also eliminate the task of running the belt between the fingers to undo any twist before engaging the belt. For these reasons and others, there is a well-defined need for a seat belt that will pull out of its housing without twisting.
The construction of the twist-free seat belt can be accomplished in several different ways. The curve or concavity, across the width of the belt, could be accomplished by weaving the seat-belt fabric around a curved framework of molded plastic, or a spring-metal wire, or other framework material. The curvature could also be formed by the manner in which a belt fabric is so woven that it creates the necessary curvature in the cross section of the belt. Such framework or weaving would have a crescent-like, semicircular shape.
It could also be accomplished by weaving plastic threads alongside the fabric thread material of the seat belt. The belt could then be run through heated forming dies to form the plastic threads to create the necessary curve. Whatever material is used, such material would have a memory that would force the belt to return to a semicircular configuration, when twisted otherwise.
The twist-free belt could have other applications, such as a cargo strapping, or an animal-restraining belt. It could be used wherever a twisting belt situation was undesirable.